#include<stdio.h>

int leapyear(int year){
	return year%4==0&&year%100!=0||year%400==0 ? 29 : 28; 
}

int main(){

	int year;
	scanf("%d",&year);
	
	printf("%d年2月的天数是%d天\n", year, leapyear(year));

	return 0;
}
